A laser interferometer is a measuring tool that uses wavelengths of a periodic phenomenon, such as laser light, for accurately measuring distances. An interferometer includes one or more receivers for detecting characteristics of the light, such as the phase of the light waves. In particular, counting cycles of the light wave plays an important role in the measurement.
Noise can cause an error in the cycle count. Such an error is also referred to as a "Glitch". Glitches are undesirable, because they reduce the accuracy of the measurement being taken. Therefore, it is an important objective of interferometer measurement system designers to eliminate or minimize glitches. This can be done by keeping the magnitude of the light high enough that the interferometer measurement is relatively insensitive to noise. However, other design considerations favor a reduced light magnitude.
A laser interferometer measurement system that reduces glitches would allow laser signals of smaller intensity to be used. Also, glitch reduction would result in more accurate and efficient positioning.